<!DOCTYPE html>
<html>

<head>
    <title>我的网页</title>
    <meta charset="UTF-8">
</head>

<body>
    <h1 align="left">一级标题</h1>
    <h2 align="center">二级标题</h2>
    <h3 align="right">三级标题</h3>
    <h4>四级标题</h4>
    <h5>五级标题</h5>
    <h6>六级标题</h6>

</body>

</html>